On-line apnea-bradycardia detection using hidden semi-Markov models.

International audienceIn this work, we propose a detection method that exploits not only the instantaneous values, but also the intrinsic dynamics of the RR series, for the detection of apnea-bradycardia episodes in preterm infants. A hidden semi-Markov model is proposed to represent and characterize the temporal evolution of observed RR series and different pre-processing methods of these series are investigated. This approach is quantitatively evaluated through synthetic and real signals, the latter being acquired in neonatal intensive care units (NICU). Compared to two conventional detectors used in NICU our best detector shows an improvement of around 13% in sensitivity and 7% in specificity. Furthermore, a reduced detection delay of approximately 3 seconds is obtained with respect to conventional detectors

Time-frequency relationships between heart rate and respiration: A diagnosis tool for late onset sepsis in sick premature infants

International audienceThe diagnosis of late onset sepsis in premature infants remains difficult because clinical signs are subtle and non-specific and none of the laboratory tests, including CRP and blood culture, have high predictive accuracy. Heart rate variability (HRV) analysis emerges as a promising diagnostic tool. Entropy and long-range fractal correlation are decreased in premature infants with proven sepsis. Besides this, respiration and its relations to HRV appear to be less. The objective of this study was to determine if analysis of time-frequency correlations between the heart rate and respiration amplitude may help for the diagnosis of infection in premature infants. An estimator of the linear relationship between nonstationary signals, recently introduced, is explored. The tests were performed on a cohort study of 60 premature infants. The results show that the correlation in the low frequency band tended to be higher in the sepsis group

L'arbre fontaine

Dans certaines régions montagneuses régulièrement ventées, soumises à un climat océanique comme au Chili, en Afrique du Sud ou au Cap-Vert, une mer de brouillard règne en quasi permanence. Ces conditions météorologiques très singulières permettent à la végétation de prospérer malgré de faibles pluies. Arbres et arbustes captent l'eau des brouillards et des bruines, donnant naissance à de véritables forêts dites nébuleuses. Ces fontaines végétales sont exploitées par l'homme depuis la nuit des temps pour récupérer de l'eau potable et développer une vie agricole. Véritable don des dieux, l'arbre fontaine a parfois été élevé au rang d'arbre sacré comme dans l'île de Hierro aux Canaries, point de départ de la recherche des auteurs de cet article. (Résumé d'auteur

A model-based approach for the evaluation of vagal and sympathetic activities in a newborn lamb.

International audienceThis paper proposes a baroreflex model and a recursive identification method to estimate the time-varying vagal and sympathetic contributions to heart rate variability during autonomic maneuvers. The baroreflex model includes baroreceptors, cardiovascular control center, parasympathetic and sympathetic pathways. The gains of the global afferent sympathetic and vagal pathways are identified recursively. The method has been validated on data from newborn lambs, which have been acquired during the application of an autonomic maneuver, without medication and under beta-blockers. Results show a close match between experimental and simulated signals under both conditions. The vagal and sympathetic contributions have been simulated and, as expected, it is possible to observe different baroreflex responses under beta-blockers compared to baseline conditions

Геофизические особенности Верхнеюрского разреза месторождений углеводородов Томской области

Использованы петрофизические уравнения и данные геофизических исследований скважин месторождений углеводородов Томской области. Выявлены петрофизические типы коллекторов горизонта Ю1 и геофизические особенности пород баженовской свиты в разрезах с разным типом коллекторов

Plasma levels of ghrelin, des-acyl ghrelin and LEAP2 in children with obesity: Correlation with age and insulin resistance

Objective: The octanoylated peptide hormone ghrelin regulates appetite and glycaemic control. Des-acyl ghrelin abolishes some effects of ghrelin, but does not bind to ghrelin receptor. LEAP2 is a novel ligand for ghrelin receptor that blocks the effects of ghrelin. Some evidences show that plasma levels of these peptides are altered adults with obesity, but their levels in childhood obesity remain poorly studied. Therefore, the objective of this study was to assess fasting plasma levels of ghrelin, des-acyl ghrelin and LEAP2 in children with normoweight, overweight/obesity and their association with different anthropometric and metabolic variables. Design: A total of 42 females and 40 males, ages 3-12 years-old were enrolled as a cross-sectional cohort. Results: Plasma levels of des-acyl ghrelin and LEAP2 (but not ghrelin) were lower and ghrelin/des-acyl ghrelin ratio was higher in children with overweight/obesity. Des-acyl ghrelin negatively correlated with age, BMI z-score, insulin and HOMA index, and the correlations were stronger in children with overweight/obesity. LEAP2 levels negatively correlated with BMI z-score. No gender differences were found. Conclusions: Our findings suggest that ghrelin tone is increased in childhood obesity, due to a decrease on plasma levels of des-acyl ghrelin and LEAP2, and that des-acyl ghrelin is associated to insulin resistance, particularly in children with overweight/obesity.Fil: Fittipaldi, Antonela Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Hernandez, Julieta. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de La Plata. Instituto de Desarrollo e Investigaciones Pediátricas; ArgentinaFil: Castrogiovanni, Daniel Cayetano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Lufrano, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: de Francesco, Pablo Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Garrido, Verónica. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de La Plata. Instituto de Desarrollo e Investigaciones Pediátricas; ArgentinaFil: Vitaux, Patrick. Bertin Technologies; FranciaFil: Fasano, María Victoria. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Matemáticas; Argentina. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de La Plata. Instituto de Desarrollo e Investigaciones Pediátricas; ArgentinaFil: Fehrentz, Jean Alain. Bertin Technologies; Francia. Université Montpellier II; FranciaFil: Fernández, Adriana. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de La Plata. Instituto de Desarrollo e Investigaciones Pediátricas; ArgentinaFil: Andreoli, María F.. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de La Plata. Instituto de Desarrollo e Investigaciones Pediátricas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentin

Optogenetic Light Sensors in Human Retinal Organoids

Optogenetic technologies paved the way to dissect complex neural circuits and monitor neural activity using light in animals. In retinal disease, optogenetics has been used as a therapeutic modality to reanimate the retina after the loss of photoreceptor outer segments. However, it is not clear today which ones of the great diversity of microbial opsins are best suited for therapeutic applications in human retinas as cell lines, primary cell cultures and animal models do not predict expression patterns of microbial opsins in human retinal cells. Therefore, we sought to generate retinal organoids derived from human induced pluripotent stem cells (hiPSCs) as a screening tool to explore the membrane trafficking efficacy of some recently described microbial opsins. We tested both depolarizing and hyperpolarizing microbial opsins including CatCh, ChrimsonR, ReaChR, eNpHR 3.0, and Jaws. The membrane localization of eNpHR 3.0, ReaChR, and Jaws was the highest, likely due to their additional endoplasmic reticulum (ER) release and membrane trafficking signals. In the case of opsins that were not engineered to improve trafficking efficiency in mammalian cells such as CatCh and ChrimsonR, membrane localization was less efficient. Protein accumulation in organelles such as ER and Golgi was observed at high doses with CatCh and ER retention lead to an unfolded protein response. Also, cytoplasmic localization was observed at high doses of ChrimsonR. Our results collectively suggest that retinal organoids derived from hiPSCs can be used to predict the subcellular fate of optogenetic proteins in a human retinal context. Such organoids are also versatile tools to validate other gene therapy products and drug molecules

Hemoglobin and Clinical Outcomes in the Vericiguat Global Study in Patients With Heart Failure and Reduced Ejection Fraction (VICTORIA)

BACKGROUND: In the VICTORIA trial (Vericiguat Global Study in Patients with Heart Failure with Reduced Ejection Fraction), anemia occurred more often in patients treated with vericiguat (7.6%) than with placebo (5.7%). We explored the association between vericiguat, randomization hemoglobin, development of anemia, and whether the benefit of vericiguat related to baseline hemoglobin. METHODS: Anemia was defined as hemoglobin <13.0 g/dL in men and <12.0 g/dL in women (World Health Organization Anemia). Adverse events reported as anemia were also evaluated. We assessed the risk-adjusted relationship between hemoglobin and hematocrit with the primary outcome (composite of cardiovascular death or heart failure hospitalization) and the time-updated hemoglobin relationship to outcomes. RESULTS: At baseline, 1719 (35.7%) patients had World Health Organization anemia; median hemoglobin was 13.4 g/L (25th, 75th percentile: 12.1, 14.7 g/dL). At 16 weeks from randomization, 1643 patients had World Health Organization anemia (284 new for vericiguat and 219 for placebo), which occurred more often with vericiguat than placebo (P<0.001). After 16 weeks, no further decline in hemoglobin occurred over 96 weeks of follow-up and the ratio of hemoglobin/hematocrit remained constant. Overall, adverse event anemia occurred in 342 patients (7.1%). A lower hemoglobin was unrelated to the treatment benefit of vericiguat (versus placebo) on the primary outcome. In addition, analysis of time-updated hemoglobin revealed no association with the treatment effect of vericiguat (versus placebo) on the primary outcome. CONCLUSIONS: Anemia was common at randomization and lower hemoglobin was associated with a greater frequency of clinical events. Although vericiguat modestly lowered hemoglobin by 16 weeks, this effect did not further progress nor was it related to the treatment benefit of vericiguat. Registration: URL: https://www.clinicaltrials.gov: Unique identifier: NCT02861534

Genome sequence of Desulfurella amilsii strain TR1 and comparative genomics of Desulfurellaceae family

The acidotolerant sulfur reducer Desulfurella amilsii was isolated from sediments of Tinto river, an extremely acidic environment. Its ability to grow in a broad range of pH and to tolerate certain heavy metals offers potential for metal recovery processes. Here we report its high-quality draft genome sequence and compare it to the available genome sequences of other members of Desulfurellaceae family: D. acetivorans, D. multipotens, Hippea maritima, H. alviniae, H. medeae and H. jasoniae. For most species, pairwise comparisons for average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) revealed ANI values from 67.5 to 80% and DDH values from 12.9 to 24.2%. D. acetivorans and D. multipotens, however, surpassed the estimated thresholds of species definition for both DDH (98.6%) and ANI (88.1%). Therefore, they should be merged to a single species. Comparative analysis of Desulfurellaceae genomes revealed different gene content for sulfur respiration between Desulfurella and Hippea species. Sulfur reductase is only encoded in D. amilsii, in which it is suggested to play a role in sulfur respiration, especially at low pH. Polysulfide reductase is only encoded in Hippea species; it is likely that this genus uses polysulfide as electron acceptor. Genes encoding thiosulfate reductase are present in all the genomes, but dissimilatory sulfite reductase is only present in Desulfurella species. Thus, thiosulfate respiration via sulfite is only likely in this genus. Although sulfur disproportionation occurs in Desulfurella species, the molecular mechanism behind this process is not yet understood, hampering a genome prediction. The metabolism of acetate in Desulfurella species can occur via the acetyl-CoA synthetase or via acetate kinase in combination with phosphate acetyltransferase, while in Hippea species, it might occur via the acetate kinase. Large differences in gene sets involved in resistance to acidic conditions were not detected among the genomes. Therefore, the regulation of those genes, or a mechanism not yet known, might be responsible for the unique ability of D. amilsii. This is the first report on comparative genomics of sulfur-reducing bacteria, which is valuable to give insight into this poorly understood metabolism, but of great potential for biotechnological purposes and of environmental significance.The authors thank CNPq (Conselho Nacional de Desenvolvimento Cientifiìco e Tecnoloìgico),organization of the Brazilian Government for supporting the doctoral study program for the development of Science and Technology. Research of IS-A and AM Stams is financed by ERC grant project 323009, and Gravitation grant project 024.002.002 fromTheNetherlands Ministry of Education, Culture and Science. Thanks to Bastian Hornung for the bioinformatics support and to Robert Smith for the English revision.info:eu-repo/semantics/publishedVersio